Precision fluid-metering valves are needed for many applications in which a precise volume of fluid must be rapidly and repetitively dispensed automatically. For example, in microdot dispensing applications manufacturers have sought a valve which could repetitively dispense 2 nanoliters, and at a rate of more than 100,000 times a day. Such a valve should be capable of turning on and shutting off in extremely small time intervals while also opening a sufficiently large flow passage to allow the desired flow. And, at the other extreme, bottle filling operations may require volumetric filling accuracies of 1% at rapid fill rates.